In this work, the activated carbon fibers(ACFs) were modified by introduction of electrolytic metal, such as Cu, in order to remove SO2. The surface properties of the ACFs were determined with FT-IR and XRD analysis. The specific surface area and pore volume were calculated from BET's equation for N2 adsorption at 77K. The SO2 adsorption of ACFs was confirmed by SO2 analysis measurement. As the experimental results, the electrolytic Cu peaks on ACFs were observed at 36° and 43°. The their intensity increased with increasing the introduction time of electrolytic Cu. However, the specific surface area and micropore volume was blocked by the electrolytic Cu. Meanwhile, the SO2 adsorption of the ACFs was significantly increased with increasing the introduction time of electrolytic Cu. It was explained that the electrolytic Cu of ACFs improved the SO2 adsorption due to the reaction between electrolytic Cu on ACFs and SO2